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Freq hopping fixes

This commit is contained in:
Piotr Krysik 2018-06-18 14:43:50 +02:00
parent 4e4a92ea05
commit 6463dc7641
3 changed files with 55 additions and 14 deletions
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1
lib/misc_utils/freq_hopping_utils.cc
View File

@ -64,6 +64,7 @@ namespace gr {
}
mai = (s + maio) % n;
}
return (mai);
}
} // namespace gsm
} // namespace gr

67
lib/trx/freq_hopping_impl.cc
View File

@ -30,6 +30,9 @@
#include "freq_hopping_impl.h"
#include "../misc_utils/freq_hopping_utils.h"
extern "C" {
#include <osmocom/gsm/gsm_utils.h>
}
namespace gr {
namespace gsm {
@ -52,7 +55,8 @@ namespace gr {
gr::io_signature::make(0, 0, 0),
gr::io_signature::make(0, 0, 0)),
d_hopping_cmd(PMT_NIL),
d_hopping_enable(false)
d_hopping_enable(false),
d_base_freq(890e6)
{
// Register I/O ports
message_port_register_in(mp("hopping_cmd"));
@ -90,6 +94,7 @@ namespace gr {
} else if(dict_ref(cmd,intern("cmd"), PMT_NIL) == intern("stop")) {
if(dict_ref(cmd,intern("fn"),PMT_NIL) != PMT_NIL){
//TODO add the command to the map<int,pmt_t>
} else {
d_hopping_enable = false;
}
@ -98,25 +103,59 @@ namespace gr {
void freq_hopping_impl::set_freq_metadata(pmt_t burst)
{
if(d_hopping_enable) {
pmt::pmt_t header_plus_burst = pmt::cdr(burst);
gsmtap_hdr *header = (gsmtap_hdr *)pmt::blob_data(header_plus_burst);
uint32_t frame_nr = be32toh(header->frame_number);
int mai = calculate_ma_sfh(d_maio, d_hsn, d_ma.size(), frame_nr);
uint16_t arfcn = d_ma[mai];
header->arfcn = htobe16(arfcn);
header->arfcn = header->arfcn | 0x8000; // set uplink flag
//oblicz czestotliwosc i ustaw w headerze
pmt_t pdu_header = car(burst);
pmt_t tx_time = dict_ref(pdu_header, intern("tx_time"),PMT_NIL);
if(tx_time != PMT_NIL){
pmt_t tx_command_time = cons(tuple_ref(tx_time,0),tuple_ref(tx_time,1));
pmt_t header_plus_burst = cdr(burst);
uint32_t frame_nr = 0;
pmt_t fn = dict_ref(pdu_header,intern("fn"),PMT_NIL);
if(fn == PMT_NIL){
gsmtap_hdr *header = (gsmtap_hdr *)blob_data(header_plus_burst);
uint32_t frame_nr = be32toh(header->frame_number);
} else {
frame_nr = to_uint64(fn);
}
int mai = calculate_ma_sfh(d_maio, d_hsn, d_ma.size(), frame_nr);
uint16_t arfcn = d_ma[mai];
// if(fn == PMT_NIL){
// header->arfcn = htobe16(arfcn);
// header->arfcn = header->arfcn | 0x8000; // set uplink flag
// }
//compute the frequences to be set in the burst header
double freq_uplink = static_cast<double>(gsm_arfcn2freq10(arfcn, 1)) * 1.0e5;
double freq_downlink = static_cast<double>(gsm_arfcn2freq10(arfcn, 0)) * 1.0e5;
pmt_t tx_command = dict_add(make_dict(),intern("lo_freq"),from_double(d_base_freq));
tx_command = dict_add(tx_command,intern("dsp_freq"),from_double(freq_uplink-d_base_freq));
tx_command = dict_add(tx_command,intern("time"),tx_command_time);
pmt_t rx_command = dict_add(make_dict(),intern("lo_freq"),from_double(d_base_freq));
rx_command = dict_add(rx_command,intern("dsp_freq"),from_double(freq_uplink-d_base_freq));
rx_command = dict_add(rx_command,intern("time"),tx_command_time);
rx_command = dict_add(rx_command,intern("direction"),intern("RX"));
pdu_header = dict_add(pdu_header, intern("tx_command"),tx_command);
// pdu_header = dict_add(pdu_header, intern("tx_command"),rx_command);
// std::cout << "arfcn " << arfcn << " mai " << mai << " d_ma.size() " << d_ma.size() << " d_hsn " << d_hsn << std::endl;
std::cout << "arfcn_uplink " << arfcn << std::endl;
// std::cout << "freq_downlink " << freq_downlink << std::endl;
// std::cout << "pdu_header " << pdu_header << std::endl;
// std::cout << "size_header_plus_burst " << length(header_plus_burst) << std::endl;
message_port_pub(mp("bursts_out"), cons(pdu_header,header_plus_burst));
}
} else {
message_port_pub(pmt::mp("bursts_out"), burst);
message_port_pub(mp("bursts_out"), burst);
}
}
bool freq_hopping_impl::set_hopping_params(pmt::pmt_t hopping_params){
bool freq_hopping_impl::set_hopping_params(pmt_t hopping_params){
bool retval = false;
if(hopping_params != PMT_NIL){
//set hopping parameters immediately

1
lib/trx/freq_hopping_impl.h
View File

@ -36,6 +36,7 @@ namespace gr {
bool d_hopping_enable; //if true block do the hopping, if not block just passes the bursts
uint64_t d_hsn; //hopping sequence number
uint64_t d_maio; //mobile allocation index offset
double d_base_freq; //local oscillator frequency
std::vector<uint64_t> d_ma; //mobile allocation
pmt::pmt_t d_hopping_cmd; //TODO: change this uint64_to a std::map